The studies concerned with rates of chemical reactions and
factor that effect the rates of
Chemical reactions and factor that affect the rates of
chemical reactions and the mechanism of
Reactions constitute the subject matter of reaction kinetics.
There are many factor effecting the
Rate of reaction
Just like nature of reactants, concentrate of reactants,
surface Area, Light, Temperature, and Catalyst.
Here, we discuss the effect of temperature on Zero, Pseudo
First, 1st, 2nd, and 3rd Order of reactions.
Effect of Temperature
on Reaction Rates
The orders of reaction are independent of temperature –
orders change only when the reaction
Thus, the entire temperature dependence of a reaction, as
expressed in a rate law, is found in the
Rate constant, k?
Think about a typical rate law: Rate = –k?Am
The rate depends on how much is there (the concentration
term, Am and how effectively what
Is there can react, k.
In this interpretation, k?is a probability factor!
, all the collision does not result in reaction. Only
effective collision can give activation energy to the molecules. To start reaction,
molecules must gain activation energy the method is a ?
because the kinetics of the single reactant can be studied
As if the concentration were first?order while the other
reactants are held almost constant because their
Concentration is so large relative to the species being
According to collision theory, rate of reaction is
proportional to the number of collision among the molecules. Thus, if frequency
of collision is increased rate of reaction is also increased .However all the
collision do not result in reaction. Only effective collision can give
activation energy to the molecules. To start reaction, molcules must gain
At low temperature mostly molecules posses average energy
and only small fraction of molecules posses necessary. Most of the molecules posses’
With increase in temperature, the fraction of molecules with
high energy increase.
The curve at higher temperature T2 has flattened .Thus,
there is widower distribution of
Velocities. At higher temperature T2, number of molecules
having high energy increases while number of molecules with energy decreases.
Thus, effective collision will be increased and rate reaction will also be
When the temperature is raised by fraction of molecules with
energy more than E, roughly doubles. Thus the rate of reaction is also doubled.